北祁连黑矿型和塞浦路斯型硫化物矿床容矿火山岩的物质来源与形成环境  

Material source and formation environment of ore-hosting volcanic rocks in Kuroko-type and Cyprus-type sulfide deposits of North Qilian Mountains

作　　者：张兰英[1] 曲晓明[1] 辛洪波[1] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037

出　　处：《矿床地质》2008年第3期345-356,共12页Mineral Deposits

基　　金：国土资源大调查项目"我国主要金属矿床模型研究"(编号1212010634001)的资助

摘　　要：文章以白银厂石英角斑岩和石居里富钠玄武岩为代表,对产于北祁连造山带的"黑矿型"和"塞浦路斯型"铜多金属块状硫化物矿床的容矿火山岩做了系统的常量元素、微量元素、稀土元素及锶、钕、铅同位素分析。结果表明,这2种火山岩均表现出俯冲带岩浆作用的特征。所不同的是,白银厂"黑矿型"块状硫化物矿床容矿火山岩形成于活动大陆边缘的陆缘弧环境;石居里"塞浦路斯型"硫化物铜矿床形成于大洋板块内部的洋生弧环境。与各自的形成环境相对应,白银厂的石英角斑岩来源于原生地幔在俯冲板片流体参与下的部分熔融,岩浆在上升侵位过程中有部分大陆地壳物质混入。石居里的富钠玄武岩同样也是产生于原生地幔在板片流体作用下的部分熔融,但没有遭受陆壳物质混染。The North Qilian orogen is one of the main metallogenic areas for sulfide deposits. Besides the sedimentation-exhalation （sedex） type Jingtieshan iron deposit, there exist lots of ＂Kuroko-type＂ and ＂Cyprus-type＂ copper polymetallic massive sulfide deposits related to acid and basic volcanism. With Baiyinchang and Shijuli areas as representatives, the authors made a systematical study of main elements, trace elements, rare elements and Sr, Nd, Pd isotopes of the ore-hosting volcanic rocks in these two types of ore deposits. The results indicate that the volcanic rocks have clear characteristics of subduction zone magmas. The difference between these two types lies in the fact that the ore-hosting volcanic rocks of the Baiyinchang ＂Kuroko-type＂ massive sulfide deposit were formed in an epicontinental arc environment of the active continental margin, whereas those of the Shijuli ＂Cyprus-type＂ sulfide copper deposit were formed in an ocean arc environment within the ocean plate. Correspondingly, the quartz keratophyre of Baiyinchang was derived from partial melting of the original mantle with the participation of the liquid of subduction plate and, during the upward migration and invasion of rnagma, the mingling of some continental crust. Similar to things of Baiyinchang, the source of the sodium-rich basalts of Shijuli came from partial melting of the original mantle with the participation of the liquid of subduction plate, but with no mingling of continental materials.

关 键 词：地质学 块状硫化物矿床 容矿火山岩 成矿构造环境 物质来源 北祁连造山带 

分 类 号：P618.41[天文地球—矿床学]